Structure and Mechanical Properties of Human Trichocyte Keratin Intermediate Filament Protein

The study developed an atomistic model of the keratin dimer using human keratin type k35 and k85 sequences, and through simulations, it was found that disulfide cross-links in a keratin tetramer increased strength by 20% and toughness by 49%, despite the loss of α-helical structures under loading. This demonstrated the significant role of disulfide bonds in the mechanical properties of trichocyte α-keratin, providing a basis for further research on hair fibrils and other fibers.